Blowout preventer



Oct. 16', 1945. H. ALLEN BLOWOUT PREVENTER Filed April 11, 1942 3Sheets-Shut 1 HERBERT. ALLEN INVENTDR Oct. 16, 1945. H. ALLEN BLowoIiTPREVENTER Filed April 11, 1942 3 Sheets-Sheet 2 HERBERT ALLEN BY afarfi. GM.

ATTORN EX.

Oct. 16, 1945. H. ALLEN 2,387,106

BLOWOUT PREVENTER Filed Agril 11, 1942 s Sheets-sheaf. s

HERBERT ALLEN INVENTO R ATTORN CY.

Patented Oct. 16. 1945 Herbert Allen,

Houston,

Tex., asslgnor to Cameronlron Works, Houston, Tex. Application April 11,1942, Serial No. 438,527

'14 Claims.

The invention relates to a blowout preventer.

In the drilling of deeper and deeper wells higher pressures areencountered and the equipment for controlling such pressures ofnecessity becomes heavier and more massive. Such heavler equipment isdimcult to handle and the present invention therefore relates to a highpressure blowout preventer wherein the pressure can be applied not onlyfor the opening and closing of the ram members, but also for the purposeof inserting and removing the ram members relative to the blowoutpreventer housing.

In the use of blowout preventers to be closed about a pipe in the wellthe ram members have a recess therein so that the two ram memberscooperate together to fit closely about the pipe and form a seal.Whenever a difierent diameter pipe is run into the well it is necessaryto change the ram so as to provide a pair of rams forming a recess whichwill fit about the particular pipe which is then in the well. In view ofthe massive construction of the ram members, the fact that they must fittightly in the chambers in the housing, and the fact that they areusually covered with heavy grease as well as grit and mud, makes thechanging of the ram a rather diflicult and timeconsuming operation. Thepresent blowout preventer has been constructed with a view of permittingquick changing of the rams and also provides a construction whereinfluid pressure can be utilized in pulling the rams from the preventerhousing so that they can be readily changed, and for also forcing therams back into the housing into an operative position.

It is one of the objects of the invention to provide a quick'change ramconstruction in high pressure blowout preventers.

Another object of the invention is to provide a blowout preventerwherein fluid pressure is utilized for removing and inserting the rams.

Still another object of the invention is to provide a blowout preventerbonnet structure to which a ram may be readily connected.

Still another object of the invention is to provide a constructionwherein a minimum number of fastening members are utilized in clampingthe bonnet to the preventer housing.

It is also an. object of the invention to provide a fluid pressuremechanism for operating the rams of a blowout preventer wherein suchmechanism can move beyond the normal stroke of the ram in order toremove the ram from the preventer housing.

Still another object of the invention is to provide a stem for blowoutpreventer rams to which the ram can be readily connected or removed butwherein the stem will hold the ram against rotation.

Still another object of the invention is to provide a minimum number ofconnecting members for a blowout preventer bonnet.

It is also an object of the invention to provide an operative yoke andbonnet assembly for blowout preventers.

A still further object of the invention is to provide anarrangement ofpacking for blowout preventer rams which can be readily attached to theramsand removed therefrom and which will form a seal about the upperhalf of the ram so as to exclude the well pressure therefrom.

Still another object of the invention is to provide a blowout preventerwherein the well pressure is applied to a greater area behind the ramthan on the forward face of the ram after the ram is closed, so that thewell pressure will tend to hold the ram in closed and sealed position.

Other and further objects of the invention will be more fully apparentwhen the following description is considered in connection with theaccompanying drawings wherein:

Fig. 1 is a side elevation, partially in section, of the assembledblowout preventer.

Fig. 2 is a, perspective view of part of the ram stem.

Fig. 3 is a perspective view of the ram member disconnected from thestem.

Fig. 4 is a top plan view looking down on the blowout preventer with oneof the operating cylinders in section and showing the rams as havingbeen withdrawn from the housing by the application of fluid pressure.

Fig.5 is a top plan view with-the rams in closed position and thebonnets connected to the preventer body.

Fig. 6 is a transverse section taken on the line 6-6 of Fig. 4 andshowing the construction of the ram, packing and stem.

In Fig. 1 the blowout preventer body is shown at 2 and preferably hasthe upper and lower flanges 3' by which it is connected to the wellhead. This body has th vertical passage 4 and the ram chambers 5therein. Each of the chambers 5 is closed by the bonnet assembly 1 whichis connected to the body by a plurality of stud bolts 8 which projectfrom the body and pass through suitable openings in the flange 9 of thebonnet. It is important to note that in the form shown in the drawingsonly four of these studs a have been provided andthat each stud isarranged to receive a hammer lug nut it. These and have the lugs IIthereon which are adapted to be struck with a hammer in. order totighten and loosen the nuts. They are .of such large diameterthat theymay be tightened very securely and in this manner clamp the bonnetrigidly to the body. Heretotore some twenty to twentyfour stud boltshave been used in connecting the flanges, so that it should be apparentthat a tremendous saving of time and energy has been eflected byproviding but four such nuts.

The bonnet assembly is made up of the flange 9 which is arranged to fitagainst the end face I! of the extension which provides the ram chamber5. This flange carries a yoke l4 having a bearing l5 therein which isthreaded to receive the spindle it. -This spindle is rotatably mountedso that it may be turned to abut a head or crossarm l8 which extendsthrough the yoke 14 to force the arm toward the housing by manual forceor to lock the arm against outward movement. A ram stem 20 is threadedat 2| into this crossarm and extends through a packing assembly 22 inthe flange 9.

The inner end or this stem has a non-circular lug 24 thereon. which isspaced by a neck portion 25 from the head 28 on the stem. Thisconstruction is provided in order to receive the ram 21 which has achannel 25 extending transversely of the rear end 29 of the ram andspaced inwardly from the end by the flanges 30. This channel 28 is or awidth to receive the head 25, with the lug 24 sliding in the groovebetween the inner edges of the flanges 30. The ram will drop down overthe head until it arrives at the position shown in Fig. 1, and when thuspositioned the ram is held against rotation relative to the stem 20, andthe stem 20 is firmly secured by the threads 2| in the crossarm l8.

In order to reciprocate the ram from the open position of Fig. 1 to theclosed position of Fig. 5, the piston rods 35 are connected to each endof each ofthe crossarms l8 and secured to the arm by the nuts 35. Eachof these piston rods extends through the cap 3'! on the end of apressure or operating cylinder 38, one of these cylinders beingpositioned at each side of the preventer body and supported thereon bythe arms 39. The cylinders are removable relative to the arms bydisconnecting the retainer blocks 40.

Each oi. the cylinders 38 contains a pair or pistons 4 i, one of whichis positioned on each or the rods 35 in order to control the movement ofthe rams. Each piston is slidably mounted in its cylinder.

With the parts in the position of Fig. 4 with the rams 21 inserted overthe head 26 and in position to be moved into the chamber 5, the pistonswill be at the outer ends of the cylinders.

In order to move the pistons a fluid pressure control piping is shown at43. This arrangement includes the control valve 44 which can admit orrelease pressure through the piping 45 to a,aav,1oe'

' nuts, as best seen in Fig. 5, are relatively massive each other,causing the crossarm i8 and the bonnet construction to move inwardly,thus forcing the rams into the chambers 5. Any desired pressure may beapplied and the rams forced into the each end of the cylinders 38, andan additional connection to admit or release pressure at the centers ofthe cylinders through the ports 41. The connection 48 may lead from asource of pressure, and the rear side oi. the valve 44 (not shown) maycontain an exhaust or release for the pressure from either the pipes 45or 46. In this manner the single valve 44 will serve to manipulate thepistons and the rams.

With the parts in the position of Fig. 4, it pressure is admitted to theends 45, the pistons at the opposite ends of the cylinder will movetoward housing. The bonnet flange 8 is brought against the face i3 sothat the hammer lug nuts i0 may be employed to anchor the bonnetto thebody.

It seems apparent from the relative position of the parts in Fig. 4 thatwhen either bonnet is connected and the corresponding ram is retracteduntil it engages the bonnet as in Fig. l, the pistons 4! connected toeach ram will not have moved to the centers of their respectivecylinders but that there will be a sufllcient additional space in eachcylinder to permit additional movement oi the pistons so as to eflectthe closing of the "ram by sliding opposite ram assemblies toward eachother, as seen in the position of Fig. 5. This sliding movement ispermitted by the spindle I6 because such spindle merely abuts the arm i8but by tightening oi the spindle It, the ram can be locked in closedposition or it can be closed by manual operation of the spindle.

During the normal operation of the rams in actual practice, when therams are closed the pistons will be in the position of Fig. 5. Whenpressure is introduced at the port 4! the pistons will move out untilthe .ram abuts the flange I oi! the bonnet. at which time the pistonswill have moved outwardly for only a portion of the length of thecylinder. When, however, it is desired to withdraw the rams for repairor to change rams, the hammer lug nuts ill will be loosened and removedand the application or pressure at the port 41 will be efiective to movethe pistons beyond their normal stroke in operating the rams and toapply pressure to withdraw the rams to the position of Fig. 4, pullingthem out of the housing completely.

Each ram may have a threaded socket ll therein to which a bolt orspindle can be connected so that a hoist may be used to lift the ramfrom the stem in changing the ram. In inserting the ram, the reverseprocedure will be followed.

The ram construction is best seen in Figs. 3

and 6 wherein the metal body 5| of the ram is shown as having aplurality of grooves 52 therearound which will receive grease orlubricant to lubricate the movement or the ram. A particular type ofpacking 53 is shown as extending across the front face and along thesides oi. the ram. This packing is the same as that disclosed in myprior Patent No. 2,194,255 granted March 19, 1940.

In order to provide a seal around the upper or crown portion of the rearof the ram, 9. special packing 54 has been provided. This packing isseen in section in Fig. 6 as having been deposited in a groove 55 whichis somewhat more than a semi-circle. The packing is a body of rubber orsimilar material 55 with a springlike member 51 incorporated thereinwhich is somewhat resilient so that the portion or end 58 of the packingtends to snap over the ram and the resiliency or the member 51 tends tohold the packing in place. The ends 59 of this member extend to theinner face or the packing so as to position it rigidly against the baseof the groove. This packing abuts against the ends or the lug portions60 of the side packing 53 so that a. complete seal is formed across theface or the ram, at the center and around the top and rear portion ofthe ram. The discontinuity of the packing 54 around the bottom of theram leaves space for and permits aeamoe the ram to have a groove or slotti in its lower face which extends axially of the ram to at pressureinto the rear portion 02 of the chamber 5 behind the ram. Thus, when theram is open, the total forces exerted by the pressure on the front andrear surfaces of the ram will be eqized, except that the total forceexerted on the front of the ram will exceed that on the rear of the ramby an amount equal to the total force front face of the ram, plus, orcourse, a cient amount oi force to overcome friction. The ram may,therefore, be moved with only a fraction of the external force whichwould be necessary if the pressures on the front and rear faces of theram were not equalized to the extent indicated.

as the ram moves to closed position around the pipe, however, thepacking 53 will form a seal with the pipe and the side 80 will form a"seal with the preventer. housing. These seals cut off the well pressurefrom the upper forward part 65 of the ram, while the entire rear face ofthe ram is still exposed to the well pressure. Thus, if the rams areclosed and sealed there will be a predominating pressure on the rear ofthe ram from the well, tending to hold the ram closed. This is truebecause of the extent of the sealing of the packing 5d, the lugs 00 andthe front packm 53.

It seems apparent that a very high pressure ratio for closing the ramshas been provided and with the design of the parts as actually used, the

pressure ratio is about to 1 so that, for in stance, if a source ofpressure of, say 1000 pounds is available in the piping at, then theblowout preventer could be closed against a well pressure of 10,000pounds. This is true because the area of the two pistons tending toclose each ram is ten times the area of the ram stem or screw, while thearea of the ram itself is balanced ex cept for themes, of the stem,

In operation it is probable that one or the other of the rams may slidemore readily than the other so that one ram may close and then anincrease or a continuation of the pressure may cause the other ram toclose.

Broadly, the invention contemplates a high pressure fluid operatedblowout preventer wherein the rams can be quickly changed and aremanipulated by fluid pressure.

What is claimed is:

l. A high pressure blowout preventer including a body, ram chamberstherein, a ram in each chamber, a head closing each chamber, a stemextending through each head and connected to the ram, a. crossarm oneach stem, a piston con= nected to each end of the crossarm, and a pressure cylinder at each side of the body in which the two pistons on thesame end of the body are movable by the application of pressure so as toopen or close both rams.

2. A high pressure blowout preventer including a body, ram chamberstherein, a ram in each chamber, a head closing each chambena stemextending through each head and connected to the ram, a crossarm on eachstem, a piston connected to each end of the crossarm, and a pressurecylinder at each side of the body in which the two pistons on the sameend of the body are movable by the application of pressure so as to openor close both rams, said cylinders being of a length to permit movementof said pistons to efiect withdrawal of said rams fromthe body uponrelease of said heads.

3. A high pressure blowout preventer including a body, ram chamberstherein, a ram in'each chamber, a head closing each chamber, 'astemextending through each head and connected to the ram, a orossarm on eachstem, a piston con--- nected to each end of the crossarm, a pressurecylinder at each side of the body in which the two pistons on the sameend of the body are movable by the application of pressure so as to openor close both rams, said cylinders being of a length to permit movementof said pistons to efiect withdrawal of said rams from the body uponrelease of said heads, and means which are half and less than the fullcircumference of the 1 ram, and a springlike reenforcing member there=quickly operable to aihx and release said head relative to said body.

4. A blowout preventer including a body having a vertical passagetherethrough, rams therein movable transversely to open or close saidpassage, means to move said rams including pressure cylinders onopposite sides of said rams and a connection from a piston in each ofsaid cylinders to each of said rams, and means to control the how ofpressure to the cylinders to move the pistons so that said rams may beforced into or withdrawn from said body.

5. In a blowout preventer having a body a well passage therethru,lateral chambers extending from the passage, and rams movable therein toclose the passage, means to move said rams including a pair of hydrauliccylinders, pistons in each cylinder connected to each ram, saidcylinders being constructed to actuate said pistons to withdraw saidrams from the body.

6. A packing for circular rams to seal the upper portion thereof in theram cylinder including a curved portion somewhat in excess of onein toclamp said packing to the ram as it passes beyond a diameter of the ram.

7. In combination with a ram type of blowout preventer for wells 9, pairof power cylinders on opposite sides of the rams for operating the ramsof the blowout preventer, a pair of pistons in each cylinder, one pistonin each cylinder being connected to each ram, means to introducepressure fluid into said cylinders respectively between the pistonstherein to open the rams and behind the pistons to close the rams.

8. A power cylinder for operating the rams of a blowout preventena, pairof pistons in said cylinder each of which is connectable to a ram, meansto introduce pressure fluid into said cylinder between the pistons toopen the ra ms and behind the pistons to close the rams, said cylinderbeing of a length to move the pistons beyond the travel required fornormal operation so that such abnormal movement will effect withdrawalof the rams from the preventer.

9. A ram and head assembly for blowout pre venters including a head, aram stem slidable therethrough, a. ram removably positioned on saidstem, a U-shaped yoke on said head, a crossarm connected to move saidstem and extending through said yoke, power means connected to saidcrossarm to move said stem, ram, and crossarm with respect to said headand yoke, and a locking spindle threaded through said yoke to move or tolock said stem and crossarm.

10. A ram and head assembly for hydraulically tionol'said yoke,hydraulicpower means connected to the laterallyextending parts or saidcrossarm to move said stem, ram and crossarm with respect to said headand yoke, and a lock member on said yoke movable against saidcrossasa'moe means connected to said crosshead at a positiontions toprevent rotation of said ram, and power spaced from said stem to movesaid stem, ram and crosshead with respect to said head and yoke.

13. A blowout preventer for wells, including a body, a pair of ramsmounted in slideways therein .k

v and slidable toward and away from each other am to confine or limitthe-movement of the stem and ram.

11. A ram for blowout preventers including a I cylindrical body, alongitudinal passage along the underside of said body, a packing acrossthe front across the upper portion only of the ram at the rear andcrossing the ends of the side packings, and a crown type oi packing insaid groove including an arcuate springlike reenforcing and retainingmeans in said crown packing and extending' more than halfway and lessthan completely around said body to inherentlyihold the packing in thegroove 12;. A ram and head assembly for blowout preventers, including ahead, a ram stem slidable therethrough, a ram reinovably positioned onsaid stem, an open U-shaped yoke on said head, and

a power operated crosshead on said stem extending through said yoke tomove said ram, said stem and ram having non-circular en agin p rlo, andalong the sides of said body, a packing groove x ment or the ram.

to close the well passage, means carried by said body to simultaneouslyapply an equal and uniform pressure to actuate each of said rams, saidrams being removable from said means'in a lateral direction with respectto the direction of movement oi the rams in said slideways, said meansbeing of an extent to withdraw and support the rams outside of said bodyand beyond said slideways to permit such lateral movement of the rams.

14. A device of the character described, comprising a body having aslideway therein, and a passage therethrough, -ram mounted in saidslideway and slidable toward and from said passage, means carried bysaid body to actuate said ram, said ram being removable from said meansin a lateral direction with respect to the direction of movement of theram in said slideway, and said means being of an extent to withdraw andto support said ram outside of said body and beyond said slideway and topermit such lateral move- HER BERT v ALLEN.

